Human memory is quirky, complicated, and unreliable. Even when we think we're remembering everything accurately, chances are things have gotten twisted along the way. Let’s take a look at why your memory sucks, and how you can change that.

Science is still figuring out all kinds of new things about our brains and memory. What we do know is that a lot of people struggle with remembering things, and in many different ways. Perhaps you're always forgetting a few items at the grocery store, or to pick up the dry cleaning on your way home. Worse, maybe you can't remember events from your childhood that well, or you remember an event from college differently than a friend. So, let's take a look at what's really going on in your brain, and then see if we can actually do anything to improve your memory.

Why Your Memory Is Terrible

Everyone's memory is different, but none of us have a perfect memory. In fact, even if you think your memory is perfect, chances are it isn't. To understand how this works, we need to look at a few different things, starting with how we remember anything to begin with.

Why You Remember What You Remember

The fact is, human memory is complicated. As an example, consider how you remember visual images. It seems straightforward, you see something, and you remember it. But as Scientific American points out, it's more complex than that:

Memories of visual images (e.g., dinner plates) are stored in what is called visual memory. Our minds use visual memory to perform even the simplest of computations; from remembering the face of someone we’ve just met, to remembering what time it was last we checked...

Memories like what you had for dinner are stored in visual short-term memory—particularly, in a kind of short-term memory often called “visual working memory.” Visual working memory is where visual images are temporarily stored while your mind works away at other tasks—like a whiteboard on which things are briefly written and then wiped away.

So, what causes those memories to stick around and not be wiped away from that whiteboard? According to a one study from MIT, it might simply be how meaningful an image is and if we can connect it to other knowledge. If you can connect that image to something else, it increases the chances you'll remember it later. Like learning, memory is all about context. This is why, as The Atlantic points out, pattern recognition is key. Essentially, the more connections a new memory has to knowledge you have, the more likely it is you'll remember that information. The same basic process seems to happen with most memories.

Experts believe that the hippocampus, along with another part of the brain called the frontal cortex, is responsible for analyzing these various sensory inputs and deciding if they're worth remembering. If they are, they may become part of your long-term memory... these various bits of information are then stored in different parts of the brain. How these bits and pieces are later identified and retrieved to form a cohesive memory, however, is not yet known...

To properly encode a memory, you must first be paying attention. Since you cannot pay attention to everything all the time, most of what you encounter every day is simply filtered out, and only a few stimuli pass into your conscious awareness... What we do know is that how you pay attention to information may be the most important factor in how much of it you actually remember.

The fact of the matter is, we're still learning a lot about human memory. Why we remember certain details over others is still a mystery.

Memories Are Fallible

It's probably no secret to you that you can't trust your memory. All of us have had moments where we've misremembered a detail, forgotten something, or even made details up completely. The reason is pretty simple: our memory isn't always reliable because it's about perception.

Most people have so-called flashbulb memories of where they were and what they were doing when something momentous happened: the assassination of President John F. Kennedy, say, or the explosion of the space shuttle Challenger. (Unfortunately, staggeringly terrible news seems to come out of the blue more often than staggeringly good news.) But as clear and detailed as these memories feel, psychologists find they are surprisingly inaccurate.

Nader, a neuroscientist at McGill University in Montreal, says his memory of the World Trade Center attack has played a few tricks on him. He recalled seeing television footage on September 11 of the first plane hitting the north tower of the World Trade Center. But he was surprised to learn that such footage aired for the first time the following day. Apparently he wasn’t alone: a 2003 study of 569 college students found that 73 percent shared this misperception.

It's not just traumatic events that cause our memories to flake out. One study in The Journal of the Association for Psychological Science points out that simply recalling memories enhances and distorts them. Which is to say, when you remember something you're actively changing it. In part this has a lot to do with a wide variety of memory biases that color the ways we remember. From the positivity effect where we tend to remember the positive over the negative to the egocentric bias where we remember ourselves as being better than we are, we're constantly changing memories in a way that benefits how we view ourselves. Which is to say, trusting your own memory isn't always the best idea.

For example, one study published in The Journal of Experimental Psychology showed that we tend to think we'll remember something important more than we will. This is essentially when you don't write down a brilliant idea because it's good you'll never forget it, and then you immediately forget what it was. It's happened to the best of us, and it's because we're overly confident in our ability to remember.

Unfortunately, like most of our biases, the only way to really counteract them is to know they're there. Knowing that your memory isn't perfect means you'll pay more attention to those imperfections in the future.

What You Can Do to Improve Your Memory

Improving your memory is possible, but despite what the self-help section at your local bookstore might say, it's not just about a series of mental hoops you can jump through every day. In fact, while there certainly are some techniques proven to help you retain information, improving your memory is just as much about lifestyle as anything else.

What all of this new research suggests, says Teresa Liu-Ambrose, an associate professor in the Brain Research Center at the University of British Columbia who oversaw the experiments with older women, is that for the most robust brain health, it’s probably advisable to incorporate both aerobic and resistance training. It seems that each type of exercise “selectively targets different aspects of cognition,” she says, probably by sparking the release of different proteins in the body and brain...

Well, it turns out that probably all the stages of sleep are involved, but they're involved in different ways. And so what we will classically do is we'll train subjects on some memory task, and it might be a list of words, or it might be a typing sequence. So it can be very different types of memory problems...

And what we see pretty consistently is that the ones who got a chance to sleep will actually be performing much better after that 12 hours than the ones who had been awake... So on one task it might be the amount of deep sleep you get early in the night, and this would be the case more for things like verbal memory, that you'll see that the amount of improvement subjects show after sleep will depend on how much of that slow wave, that deep sleep they get, whereas in other tasks it might correlate with the amount of REM sleep that they get.

Some of the most insidious effects of too little sleep involve mental processes like learning, memory, judgment and problem-solving. During sleep, new learning and memory pathways become encoded in the brain, and adequate sleep is necessary for those pathways to work optimally. People who are well rested are better able to learn a task and more likely to remember what they learned. The cognitive decline that so often accompanies aging may in part result from chronically poor sleep.

Case in point, a good night's rest really can improve your memory in the long term. The good news is that rebooting your sleep schedule isn't that hard to do. If you stick with it, your memory should stay strong.

Try These Memorization Techniques

In the end, your memory probably isn't as bad as you think. It just takes some regular maintenance and a little training to keep it in shape. You can't magically just improve your memory by studying. If you're the type who forgets your keys, you'll probably always do so. That said, you can employ certain techniques to help you with memory retention, and perhaps more importantly, your initial perception. We've talked about this a lot in the past, so here are a few places to get started:

Improve your memory with the chunking technique: The chunking technique uses the pattern recognition we talked about in the first section to help you remember things. In the simplest terms, it's like remembering a phone number using the letters on a phone's dial pad instead of just the numbers.

Combine information with bizarre images: If you need to remember a certain set of details, it's often easier for us to do so when we combine that information with something crazy. So, if you need to remember milk and bananas at the grocery store, remember a giant banana with a hatchet chasing after a cow that's ready to burst with milk.

Use a mnemonic peg system: This one's a bit complicated, but a peg system essentially lists items as a rhyme so it's easier to remember. Once an item is pegged to the list, you can usually recall that information later.

Memory is weird, and it works in strange ways. It's unreliable, but we still have to put our trust in it. Memory is hard to work with, but it's still malleable and you can force memories into your brain. Science is still figuring out exactly what works best, but for now it seems like few things trump a good night's rest and exercise.